Emission driver and organic light emitting display device having the same

1. An organic light emitting display device comprising:

a display panel comprising a plurality of scan lines, a plurality of data lines, a plurality of emission lines, and a plurality of pixels;

a scan driver configured to provide a scan signal to the pixels via the scan lines;

a data driver configured to provide a data signal to the pixels via the data lines;

an emission driver comprising a plurality of emission stages for providing an emission signal to the pixels via the emission lines; and

a controller configured to control the scan driver, the data driver, and the emission driver,

wherein each of the emission stages comprises a plurality of sub-stages dependently connected to each other,

wherein one of the sub-stages is configured to output the emission signal to one of the emission lines,

wherein the controller is configured to provide a plurality of scan clock signals for controlling the scan driver to the scan driver, and to provide a plurality of emission clock signals for controlling the emission driver to the emission driver, and

wherein a period of the scan clock signals is longer than a period of the emission clock signals.

2. The organic light emitting display device of claim 1 , wherein the sub-stages comprise:

first and second sub-stages each configured to provide an output signal, which is generated by shifting a corresponding input signal to be synchronized with a first emission clock signal of the emission clock signals or a second emission clock signal of the emission clock signals, to a next sub-stage, and

wherein one of the first and second sub-stages is configured to output the output signal as the emission signal to one of the emission lines.

3. The organic light emitting display device of claim 2 , wherein the second emission clock signal is substantially the same as the first emission clock signal shifted by a half period of the first emission clock signal.

4. The organic light emitting display device of claim 2 , wherein each of the emission stages further comprises:

an output signal selector configured to select one of the output signal of the first sub-stage and the output signal of the second sub-stage as the emission signal.

5. The organic light emitting display device of claim 2 , wherein the first sub-stage is located opposite to the second sub-stage with respect to an emission clock line via which one of the emission clock signals is configured to be provided.

6. The organic light emitting display device of claim 1 , wherein the sub-stages comprise:

first to fourth sub-stages configured to provide an output signal, which is generated by shifting an input signal to be synchronized with a first emission clock signal of the emission clock signals or a second emission clock signal of the emission clock signals, to a corresponding next sub-stage, and

wherein one of the first to fourth sub-stages is configured to output the output signal as the emission signal to one of the emission lines.

7. The organic light emitting display device of claim 1 , wherein the period of the emission clock signals are determined by dividing a period of the scan clock signals by a number of the sub-stages in one of the emission stages.

8. The organic light emitting display device of claim 1 , wherein the controller is configured to provide an emission start signal for driving the emission driver to the emission driver.

9. The organic light emitting display device of claim 8 , wherein the controller is configured to control a length of an on-period of the emission start signal based on a dimming control value for controlling a dimming level.

10. The organic light emitting display device of claim 9 , wherein the length of the on-period of the emission start signal is a multiple of the period of the emission clock signals for controlling the emission driver.

11. The organic light emitting display device of claim 10 , wherein a length of the on-period of the emission start signal corresponds to a product of a length of one horizontal period and a number of the scan lines.

12. The organic light emitting display device of claim 9 , wherein the dimming control value is configured to be changed based on an external light intensity.

13. The organic light emitting display device of claim 9 , wherein the controller is configured to provide a hybrid dimming signal to the data driver based on the dimming control value, and

wherein the data driver is configured to select one among a plurality of gamma reference voltage sets based on the hybrid dimming signal to convert image data into the data signal.

14. The organic light emitting display device of claim 1 , wherein the emission signal comprises at least one of an on-period and an off-period during one frame period.

15. A panel driver comprising:

a scan driver configured to output a scan signal to scan lines;

an emission driver comprising:

a plurality of emission stages configured to output an emission signal to a plurality of emission lines; and

a controller configured to control the scan driver and the emission driver,

wherein each of the emission stages comprises a plurality of sub-stages dependently connected to each other,

wherein one of the sub-stages is configured to output the emission signal to a corresponding one of the emission lines,

wherein the controller is configured to provide a plurality of scan clock signals for controlling the scan driver to the scan driver, and to provide a plurality of emission clock signals for controlling the emission driver to the emission driver, and

wherein a period of the scan clock signals is longer than a period of the emission clock signals.

16. The panel driver of claim 15 , wherein each of the sub-stages is configured to provide an output signal, which is generated by shifting an input signal to be synchronized with a first emission clock signal of the emission clock signals or a second emission clock signal of the emission clock signals, to a next sub-stage, and

wherein one of the sub-stages is configured to output the output signal as the emission signal to one of the emission lines.

17. The panel driver of claim 16 , wherein the input signal is an emission start signal or an output signal of a previous sub-stage, and

wherein a length of an on-period of the emission start signal is configured to be adjusted based on a dimming control value for controlling a dimming level.

18. The panel driver of claim 17 , wherein the length of the on-period of the emission start signal is a multiple of a period of the first emission clock signal.

19. The panel driver of claim 16 , wherein a length of a period of the first emission clock signal and a length of a period of the second emission clock signal are substantially the same as a length of one horizontal period.